1. Field of the Invention
The present invention relates to printing apparatuses that have a plurality of sheet feed trays and that can assign sheets to those sheet feed trays, as well as to control methods thereof and storage media.
2. Description of the Related Art
In the printing market, business models known as “print on demand” (POD), “print production”, and so on are being utilized, where printing is carried out upon receiving an order from a client and the resulting printed material, or an output product obtained by performing post-processing on the printed material, is delivered with certainty to the client by a deadline. At facilities where such printing is carried out, the ability to perform large amounts of printing at high speeds is extremely important. There are thus many cases where operators who specialize in performing various operations are assigned to printing apparatuses. Such operators specialize in performing operations such as inserting, replacing, and assigning sheets, managing print jobs, editing job tickets, conveying output products, performing post-processing such as trimming and binding, and the like. “Assigning sheets” as mentioned here refers to an operation for assigning sheet information that identifies sheets inserted or replaced by the operator to respective sheet feed trays in a printing apparatus. The printing apparatus determines which sheet feed tray contains which type of sheet based on the sheet information that has been assigned to the sheet feed trays in this manner. The inserting, replacement, and assigning of sheets is the most important operation performed by an operator. The reason for this is that if the sheets are not correctly inserted, replaced, and assigned, there is a possibility that the printing apparatus will be unable to print onto a designated sheet when executing a print job, will mistakenly print onto a different sheet, or the like. When such a situation occurs, the printing apparatus first stops the print engine and suspends the printing process. When the printing process is suspended in this manner, not only can the printing process not be restarted until the required sheets are inserted, replaced, and assigned, but the print engine must also undergo a reheating process and the like after the printing process has been restarted, and thus it takes a long time before the printing can be performed again (that is, there is a long downtime). In order to avoid such downtime, it is necessary for the operator to accurately insert, replace, and assign sheets in accordance with the print job that is to be executed, prior to the start of printing.
Meanwhile, client preferences are becoming more varied in recent years, and the types of sheets used in printing are also becoming more varied as a result. Accordingly, when assigning sheets to sheet feed trays, it is necessary for the operator to select the sheets to be assigned from among many different types of sheets, resulting in an increased likelihood of operational mistakes. To handle such a situation, a method that narrows down assignable sheet candidates based on the print job that is to be executed has been proposed. For example, according to Japanese Patent Laid-Open No. 2004-330781, only sheets that are used by the print job to be executed are displayed as assignment candidates, and thus the likelihood that the operator will mistakenly assign the sheets can be reduced. Meanwhile, according to a method disclosed in Japanese Patent Laid-Open No. 2008-055787, sheet types that cannot be fed by a sheet feed tray are deleted from assignment candidates that are displayed, and thus the likelihood that the operator will mistakenly assign the sheets to a sheet feed tray can be reduced.
According to the stated background art documents, sheets that serve as assignment candidates can be automatically narrowed down based on set conditions. However, in actual printing facilities, there are cases where operations unique to the printing facility are specified in addition to such conditions, and the sheets contained in the sheet feed trays are limited as a result. For example, there are cases where labels identifying sheets that can be contained in sheet feed trays are applied to the front surfaces of those sheet feed trays, and the operator inserts the sheets by referring to the labels. This makes it possible to reduce the likelihood of the operator inserting the incorrect sheets into the sheet feed trays. However, after the sheets have been inserted into the sheet feed tray, sheets aside from those identified by the label are to be displayed as assignment candidates when assigning the sheet information to the sheet feed tray, and thus there is still a chance that the operator will make an assignment mistake.